Update mkdocs-material requirement from ~=9.6.21 to ~=9.6.22

Updates the requirements on [mkdocs-material](https://github.com/squidfunk/mkdocs-material) to permit the latest version.
- [Release notes](https://github.com/squidfunk/mkdocs-material/releases)
- [Changelog](https://github.com/squidfunk/mkdocs-material/blob/master/CHANGELOG)
- [Commits](squidfunk/mkdocs-material@9.6.21...9.6.22)

---
updated-dependencies:
- dependency-name: mkdocs-material
  dependency-version: 9.6.22
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

requirements.txt

@@ -1,6 +1,6 @@
 # Requirements for core
 mkdocs~=1.6.1
-mkdocs-material~=9.6.21
+mkdocs-material~=9.6.22
 
 # Requirements for plugins
 mkdocs-git-committers-plugin-2~=2.5.0